Abstract
Purpose:
To evaluate the change in the use of bevacizumab (B) following the requirement for patient-specific prescriptions (PSP).
Methods:
We retrospectively analyzed the utilization of B, 0.5mg ranibizumab (R), 0.3mg ranibizumab (R-DME), and aflibercept (A) within a nine-member single retinal specialty practice over a three-month period both before (May-July 2012 [pre-PSP]) and after (May-July 2013 [post-PSP]) the requirement of PSP for B by the Ohio Board of Pharmacy. Using a Likert Scale (LS) approach (strongly disagree to strongly agree), we surveyed all nine physicians in this group practice regarding three possible reasons (PSP, efficacy, safety) for the change in drug utilization. The relative proportions were calculated; the 95% confidence intervals for those estimates were calculated using the modified Wald method. The chi-squared test of proportions was used to compare frequencies in different years. P < 0.05 was taken as being statistically significant.
Results:
There was a significant decrease in the number of B injections (Inj), going from 2,752 (61.32% of pre-PSP Inj) to 1,503 (28.61% of post-PSP Inj), a change of 1,249 B injections (-29.35% as a percent of B total injections over both years). There was a significant increase in the number of R injections, going from 1,122 (25% of pre-PSP Inj) to 1,838 (34.99% of post-PSP Inj), a change of 716 R injections (24.19% as a percent of R total Inj over both years). There was a significant increase in the number of R-DME Inj, going from 0 (0% of pre-PSP Inj; R-DME became FDA-approved in August 2012) to 429 (4.40% of post-PSP Inj), a change of 429 R-DME Inj (100% as a percent of R-DME total Inj over both years). There was a significant increase in the number of A Inj, going from 614 (13.68% of pre-PSP Inj) to 1,483 (28.23% of post-PSP Inj), a change of 869 A Inj (41.44% as a percent of A total Inj over both years). The LS results showed the following responses for decreased B use: PSP (median category, 1st quartile, 3rd quartile [M, 1st, 3rd]: all strongly agree), safety (M, 1st, 3rd : strongly disagree, strongly disagree, disagree) and efficacy (M, 1st, 3rd: all disagree).
Conclusions:
There was significantly less B utilization year over year following the requirement for PSP of B. This change corresponded more with the notion of PSP requirement than either safety or efficacy concerns in this practice.
Keywords: 460 clinical (human) or epidemiologic studies: health care delivery/economics/manpower •
748 vascular endothelial growth factor